MADRID, June 12 (Reuters) - Spain's Economy Minister Luis de Guindos on Monday said Banco Popular had sought central bank emergency liquidity on June 5 and 6, but it had ran out so quickly that the bank was left with no other option than requesting a public rescue.

"It had to request emergency liquidity from the European Central Bank on Monday and Tuesday, but on Tuesday by 1500 it had run out of liquidity and it was not in a position to ask for more because it lacked collateral," de Guindos said at a parliamentary hearing. (Reporting by Julien Toyer; Editing by Angus Berwick)